A NASA study has found that recent extreme weather events, including last year’s Texas heat wave and the Russian heat wave of 2010, are very likely to be the consequence of global warming.
The findings, published last week in the scientific paper Proceedings of the National Academy of Sciences, analyse mean summer temperatures since 1951 and show that the odds have increased over the years for “hot”, “very hot” and “extremely hot” summers. From the period between 1951 and 1980, the study shows how extremely hot temperatures covered less than 0.2% of the planet, whereas today those temperatures cover about 10% of the land area.
NASA climatologists have long collected data on global temperature anomalies, which describe how much warming or cooling regions of the world have experienced when compared with the 1951 to 1980 base period. In this study, the researchers employ a bell curve to illustrate how those anomalies are changing.
Led by one of NASA’s principal climate scientists, James. E. Hansen says:
“This is not a climate model or a prediction but actual observations of weather events and temperatures that have happened. Our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.”
Hansen says this summer is shaping up to fall into a new category, as statistics from the National Oceanic and Atmospheric Administration (NOAA), show July 2012 to be the single hottest month ever recorded in the United States. He says:
“Such anomalies were infrequent in the climate prior to the warming of the past 30 years, so statistics let us say with a high degree of confidence that we would not have had such an extreme anomaly this summer in the absence of global warming.”
In addition to NASA’s analysis, a second release of data findings from the Berkeley Earth Surface Temperature project found that average Earth surface temperature has risen by 1.5 °C over the past 250 years. The study shows a correlation between temperature records and recent atmospheric carbon dioxide level increases and points to logical reasoning that recent earth warming is anthropomorphic. This is demonstrated in one of Berkeley’s key findings charts below.
The two bodies of data validation above may help to settle ongoing controversy about the effects of climate change amongst scientists and political leaders. The new data could influence policy maker’s negotiations during key summits, such as in COP 18 in December, about how to best approach rising levels of CO2 in the atmosphere.
Information on agriculture and climate change can be found on Farming First’s website.